At a siyum the person making the siyum typically says:
הִי רָצוֹן מִלְּפָנֶיךָ ה' אלקי, כְּשֵׁם שֶׁעֲזַרֽתַּנִי לְסַיֵים מַסֶּכֶת [שם המסכת] כֵּן תּֽעַזְרֵנִי לְהַתְחִיל מַסֶּכְתּוֹת וּסֽפָרִים אַחֵרִים וּלְסַיֵימָם May it be your will, Lord, my G-d, that just as you helped me to finish Masechet [so-and-so] so shall you help me to begin other masechtot and books and finish them (Translation mine)
In a case where the siyum is made on all the masechtot (i.e. the person has completed all 6 orders of Mishna), is this text different in some way?
The question occured to me in relation to the 13th Siyum HaShas of Daf Yomi, but even a person who has learned all of Talmud Bavli might wish to go forward and learn those masechtot which have no Talmud Bavli on them. But ostensibly having learned all of Mishna, nothing called a masechta remains to the person. There are no "other masechtot" to study, though one can study these masechtot again.
Perhaps one can read the Hebrew text as "to begin masechtot & other books", which fits the Hebrew, though in fairness Artscroll translates that bit as I did.